* Offense: The Trojans open the season ranked No. 1 but the only real certainty on offense is Booty. The receivers, other than Turner, are unproven and have huge shoes to fill. The running backs, for the most part, have struggled to remain healthy. And the offensive line is a question mark because of Kalil's departure and Baker's cracked rib. Then again, there's a reason the Trojans could be double-digit favorites in every game. Talent.

* Defense: With 10 of 11 starters returning and depth at virtually every spot, this could be the nation's best defense. Could be. However, the Trojans need their defense to create more turnovers than last season and become a scoring threat. Pinkard's return after a season-ending knee injury in the 2006 opener provides flexibility in the secondary. The front seven is capable of a monstrous pass rush.

* Intangibles: Many of USC's key players have been through a championship-game run before. Experience, especially on defense, should pay off. Booty showed in the Rose Bowl against Michigan that he can carry the burden. Now he welcomes it.

* Key to the season: Like Matt Leinart before him, Booty must remain healthy. Baker and Ellis also are invaluable for a team that could play in the Bowl Championship Series title game for the third time in four years if it can avoid looking ahead.